War-aeroplane fuel-tank



G. J. MURDOCK.

WAR AEROPLANE FUEL TANK;

APPLlCATlON FILED FEB,7,1917.

Patented Aug. 10, 1920.

OrO O GEORGE J. MUBDOCK, or NEWARK, new JERSEY.

WAR-AERO PLANE FUEL-TANK.

Specification of Letters Patent. Patented A g 10 1920 Application filedFebruary 7, 1917. Serial No. 147,170.

To all whom it may concern:

Be it known that I, GEORGE J MURDOGK, a citizen of the United States,and resident of Newark, in the county of Essex, and State of- NewJersey, have invented certain new and useful Improvements inWar-Aeroplane F uel-Tanks, of which the following is a specification.

This invention relates to fuel tanks for war aeroplanes or motor cars.The objects of my invention as herein set forth are to provide means forpreventing the escape of motor fuel contained in the tank through holesmade by missiles such as bullets. Hitherto gasolene fuel tanks have beenpierced by bullets in air battles allowing the gasolene to escape on tothe aeroplane where it has been set on fire by the engine exhaust orother exposed flame. The development of steel bullets, and other highpower\ ammunition has reached a point where the weight of a tank thickenough to resist penetration has become excessive. My invention isdesigned to produce a tank so constructed as to not only prevent theescape of the fuel when punctured, but also to be comparatively light inweight.

Referring to the accompanying drawings:

Fig. I is a longitudinal sectional view showing the outer metallic shellor casing retaining resilient material under compression on all sides ofthe inner shell or casing which contains the gasolene.

Fig. II is a side elevation of the same.-

Fi III is'a cross section taken on the line X, of Fig. II.

Fig. IV is a similar cross section illustrating the conditions thatexist after a bullet has been fired through the tank.

Referring to Fig. I, the inner shell 2 is supported within theoutershell 1 by means of a stud 9, and by the pipes 7 and 8 which formrespectively the ducts through which the gasolene is introduced into thetank 2, and through which it runs by gravity to the carbureter of theengine. On one end of the container shell 1 is welded a steel, flanged,tubular fitting 6 leading into the space between the two shells, andhaving a valve 4: located so that said tubular passage may be openedor'closed. The outer end of said fitting terminates in a threaded part 5for a purpose that will be hereinafter explained.

Between the shell 1, and the outer wall of the gasolene containing tank2 a resilient material 3 preferably vulcanized rubber is lene. After therubber has been punched I believe it best to coat the outside of theparticles so formed with powdered talc by revolving the material in atumbling barrel. Coating the particles of rubber with talc causes thesmall pieces of rubber to slide by each other, and also preventsadhesion to the sides of the tank or shell when under pressure. To fillthe space between the shells with the rubber, the unit is placed in avertical position with the end 5 at the top. The small pieces of rubberare then introduced through the passage 6, and open valve 4 into thespace between the shells 1 a'nd2. When said space is entirely filled Ibelieve it the best method with my present knowledge, to fill a pumpbarrel having a screw plunger with the pieces of rubber prepared asabove described. lhe nose of the barrel is then screwed into the thread5, and the screw plunger revolved in a manner known to those skilled inthe artsoas to force the rubber particles out of the pump barrel, andinto the space betweenthe shells l and 2, thereby putting the mass ofrubber particles into a high state of compression. The valve 4 is madeof steel, and has a sharp edge so as to cut ofi the remaining rubber inthe tubular passage 6, and prevent the rubber particles containedbetween ,,the gasolene tank 2, and the outer shell 1 from being forcedout b theexpansion of the rubber particles. he force pump is thenunscrewed from the end 5, and removed.

It will be noted that the end of the tank to which the valve casing 6 isattached is rounded and preferably the opposite end of the tank is alsorounded. This permits the rubber particles to pass readily into the tankat one end, to pass down between the outer and inner shells of the tankto the other end, and to fill the space between these shells at the endof the tank opposite the valves. If the ends of the tank were at rightangles to the sides, there would be difficulty in filling the spacebetween the shells with rubber particles and a consequent diificulty insecuring the degree of compression of the rubber particles which isnecessary.

Having described the best way to make my invention with my presentknowledge, T will now describe the manner in which it is used. f

Referring to Fig. 4 it will be assumed for the purposes of thisspecification that the tank 2 has been filled with gasolene, theinduction hole 7 closed by a suitable stopper, and that the tank is,through the pipe 8 (Fig. T), in operative connection with thecarburetor, and engine. If now a bullet is fired through the unit it mayenter at 10, pass through the outer shell, the rubber under pressure,the inner shell, and the gasolene therein. The projectile in its passagethrough the outer and inner shell and the rubber may carry smallparticles of rubber with it into the tank. After passing through thegasolene the projectile strikes the opposite wall of the gasolene tank,and having pierced this passes through the rubber again, and outershell. As rubber floats on the surface of gasolene the small piecesforced into the tank by the bullet imme diately rise to the surface ofthe fluid as indicated at 12, while the holes 10, and 11 are instantlyclosed against the passage of the gasolene by the resilient character ofthe rubber under pressure, which not only closes the path made by thebullet through the rubber, but also plugs up the holes made in themetallic shells. Many holes may likewise be pierced through the uniteach being closed in like manner.

As the gasolene for the engine is taken from the bottom of the tank, andthe rubber that has been carried in by the bullets floats on the surfaceit cannot stop up the passages through which the gasolene is led to theengine, and the entrance of rubber into the eduction pipe may be furtherprevented by strainers such as .are commonly used. It may also be wiseto provide the pipe 8 with the connections leading from the tank to theengine with protection in themanner herein described as applicable tothe fuel tank. The rubber jacket around the gasolene tank also providesan efficient insulation against eX- trernes of heat or cold when flyingat high or low altitudes, thus allowing more uniform, carburation of thefuel.

The filling which I useis composed of particles of soft, resilientrubber, such as particles of rubber sponge, and this form of rubber Thave discovered swells upon being moistened with gasolene. T have foundby actual test that when this tank is punctured by a bullet, the rubberwill be forced into the puncture and form a smooth plug projectingthrough the perforation about three-eighths of an inch. The smooth plugis caused entirely by the swelling of the rubber which has becomemoistened with gasolene by the puncture of the tank. This action isassisted by the static pressure on the rubber.

It is obvious that changes in construction, and proportion of thevarious parts may be made without departing from the essential characterof this inventon. therefore do not confine myself in these or any otherunessential particulars.

What T claim is:

1. A fuel tank 'of the character described having spaced imperforatewalls, and a filler for said space of elastic material compressedbetween said walls whereby to cause said material to close a puncturecaused by the passage of a projectile through the tank.

2. A fuel tank of the character described having spaced, imperforatewalls, and rubber under compression filling said space,

said rubber acting to close a projectile puncture after the passage of aprojectile tlIIOU h the tank.

3. A fuel tank having spaced walls, the space between said walls beingfilled with particles of elastic material, the entire fillsaid walls andunder compression and acting to close a projectile puncture after thepassage of a projectile through the tank, and means for fixedly spacingsaid walls from each other and holding the walls against distortion bythe compressed material within.

6. A fuel tank of the character described including inner and outerwalls of thin sheet metal, a filling disposed between said walls andconsisting of particles of rubber, the filling being under a high degreeof compression, and means for holding said walls in spaced relationagainst the pressure of material between the walls and including tubingleading from the exterior of the tank into the interior thereof.

7. A fuel tank of the character described comprising inner and outerwalls, and a filling of elastic material disposed between said walls andunder compression and acting to close a projectile puncture after thepassage of a projectile through the tank, the tank'being provided with avalved openmitting filling and permitting its compres sion comprising avalved pipe connection to the outer wall.

9. A fuel tank of the character described comprising outer and innerwalls spaced from each other, a filling of rubber particles disposedbetween said walls under compression, and means whereby said filling maybe inserted into the space between said walls comprising a valved inlet.

10. A fuel tank of the character described comprising outer and innerwalls spaced from each other, a filling of rubber particles disposedbetween said walls under compression, means whereby said filling may beinserted into the space between said walls comprising an inlet, and avalve rotatably mounted in conjunction with the inlet and having a sharpedge.

11. A fuel tank consisting of inner and outer walls disposed in spacedrelation to eachother, a filling disposed between the walls and formedof particles of rubber, the rubber filling being under compression, oneend of the tank being rounded whereby to permit the particles to passover said rounded ends into the space between the walls forming the sideof the tank, an inlet pipe opening into said rounded end of the tank,and a valve in said pipe, the inlet pipe permitting the introduction ofthe rubber particles;

12. A self puncture-sealing tank including outer and inner imperforatewalls, and a filling of material entirely filling the space between saidwalls, said filling being elastically compressible and expansiblewhereby to permit a compression of the material upon the passage of aprojectile through the walls and an immediate expansion of the materialupon an exit of the projectile, to thereby plug the passage left by theprojectile. v

13. A self puncture-sealing tank including inner and outer imperforatewalls, and a filling of material entirely filling the space between saidwalls, said filling being elastically compressible and expansiblewhereby to permit. a compression of the material upon the passage of aprojectile through the walls and a subsequent expansion of the materialupon an exit of the projectile to thereby plug the passage left by theprojectile.

Signed at Newark, in the county of Essex and State of New Jersey this6th day of February A. D. 1917.

- GEORGE .J.- MURDOCK.

Witnesses:

J. P. MURDOCK, WM. J. MURDocK.

